garbell



Nov. 7, 1950 M. GARBELL COMPUTING mcnmn l2 Sheets-Sheet 1 Filed May 15, 1945 JNVENTOR. MAX GARBE'LL.

Nov. 7, 1950 M. GARBELL couPu'rmc momma i2 Sheets-Shem. 2

Filed May 15, 1945 Nov. 7, 1950 M. GARBELL coupu'rmc MACHINE 12 Sheets-Sheet is Filed May 15, 1945 Nm ON MN IN VEN TOR. MAx GARBELL.

HTTOEA/EV Nov. 7, 1950 M. GARBELL commune MACHINE 12 Sheets-Sheet 4 Filed May 15, 1945 INVENTOR. MAX GA RBELL.

- 1950 M. GARBELL COMPUTING MACHINE 12 Sheets-Sheet 5 Filed May 15,- 1945 INVENTOR. Max GARBELL.

ATTORNEY.

Nov, 7, 1950 M. GARBELL COMPUTING MACHINE l2 Sheets-Sheet 6 Filefi May 15, 1945 IN VEN TOR. MAX GA R8 :1. 1.

A T TORNE Y.

Nov. 7, 1950 M. GARBELL.

COMPUTING men-111m l2 Sheets-Sheet '7 Filed May 15, 1945 /zgz gg gg g ///////A INVEN TOR. Mnx Games.

ATTORNE).

Nov. 7, 1950 M. GARBELL compu'rmc MACHINE l2 Sheets-Sheet 8 Filed May 15, 1945 INVENTOR. MAX GARE 51.1..

ATTORNEK Nov. 7, 1950 M. GARBELL commune MACHINE l2 Sheets-Sheet 9 Filed lay 15,- 1945 INVENTOR. MAX GA RBELL.

N2 N2 i A TTORNE Y.

Nov. 7, 1950 M. GARBELL COMPUTING MACHINE Fil ed May 15. 1945 12 Sheets-Sheet 10 l lll I IN VEN TOR. Max GARBELL.

14 T TORNE).

Nov. 7, 1950 GAR-BELL 2,528,647

COMPUTING MACHINE Filed May 15, 1945 12 Sheets-Sheet 11 IN VEN TOR. .Mnx GARBELL.

A TTORNEK Nov. 7, 1950 M. GARBELL COMPUTING MACHINE l2 Sheets-Sheet 12 Filedk llay 15. {L945 IN VEN TOR. Max GARBELL.

ATTORNEY.

Patented Nov. 7, 195 0 COMPUTING MACHINE Max Garbell, Los Angeles, Calif., assignor to Royal Typewriter Company, Inc., New York, N. Y., a corporation of New York Application May 15, 1945, Serial No. 593,845

3 Claims. 1

The present invention relates generally to machines such as computin machines which make use'of feature key controlled means wherein the manual operation of a key determines or controls the character of the computin or other operation that will be next performed by the machine with which the operated key is associated. The invention relates more particularly to means made effective by operation of any one of a plurality of feature control keys of a computing machine, for example, to lock all of its other control keys against being operated, inadvertently or otherwise, until the operation controlled, i. e. determined by the last previously operated control key, has been completed.

The undesirable consequences that ordinarily result from the depression of a feature control key of either a manually or motor driven computing machine before a computing operation controlled by a previously depressed control key has been completed is well understood by those skilled in the art. A large per cent of computin machines today are motor driven and there are definite indications that this percentage will increase in the future. The depression of a second feature control key of a motor driven computing machine while a computing operation is then in progress will often cause extensive damage to such a machine.

An object of my present invention is to provide automatic, improved, and less expensive means which will positively prevent the operation of any one of a plurality of feature control keys of a computing or other key controlled machine before a key controlled operation thereof t1 then in progress has been completed.

Another object of my invention is the provision in a computing machine of feature control key locking devices which are operable automatically upon a small initial depression of any one of a plurality of feature control keys to look all of the other of such keys against depression before the operation of the computing mechanism under control of the operated key starts.

Another object of my present invention is the provision in a computing or other machine employin a plurality of depressible feature control keys of means which will prevent the simultaneous operative depression of more than one of such keys at the same time, i. e. instant.

Another object of my present invention is the provision in a computin machine employing several feature control keys of two Cooperating but separate and separately operable automatic means for locking temporarily against operation all of the remaining feature control keys after any one of such keys has been operated.

Another object of my invention is to provide for use in feature key controlled computing machines having computing mechanism operable manually or by motor power a first locking means made effective immediately by an initial depression of any feature control key to lock all of the other of several unoperated feature keys against operation, and a second locking means made effective subsequently by a small initial movement of the computing mechanism to look all of the unoperated feature control keys against depression on the first locking means so as to relieve some of the strain.

Another object of my invention i the provision of locking means for depressible feature control keys of a computing or other machine which means can be constructed to be applied to such a machine having a large number of control keys for locking all of the unoperated keys against depression upon a small initial movement of any one of such control keys.

It is one feature of my present invention to have two separate but cooperative key locking devices which become effective upon unoperated keys after a quite small initial operative movement of the operated key and of the main driving shaft of the machine.

It is another feature of my invention to so construct the movable parts of one of the key looking devices that these parts can be pre-assembled as a compact unit and so mounted on fixed cooperative elements of the machine.

Another feature of my present invention is the provision for application to a machine having a plurality of depressible control keys of key locking means having a set of two lockin members for each control key, each set being interconnected With all of the other sets by links which can be changed in length to secure cooperative key locking action of a large number of such locking members. Still another feature resides in the provision of a spring powered, normalizing, (i. e, restoring to normal starting positions) mean interconnected with corresponding locking members of each set so that two such means can restore all of any number, in reason, of key locking sets to normal inoperative positions. And another feature resides in an arrangement of the normalizin means whereby they also serve as power equalizing means which determine that an equal amount of depressive force on each control key locks the unoperated control keys against depression.

Other objects, features, and advantages of my present invention will appear as the description proceeds.

I have illustrated in the drawings embodiments of the present invention adapted for application to computing machine structure of the kind disclosed and claimed in my copending application, Serial No. 566,595, filed December 4, 1944, but it is to be understood that my present invention can be applied to and incorporated in other types of key controlled computing machines and is not limited for use with only such a computing machine structure as is shown and described in my above noted copending application.

Referring to the drawings which form a part of the specification:

Figure 1 shows a right hand side view of the computing machine parts which comprise a feature control key locking means and other cooperating parts associated therewith, the right hand side wall of the case and certain other parts being shown broken away in whole or in part.

Figure 2 shows a side elevational view of the feature key locking means of Figure 1, broken away in part, as the means appear when the machine is in normal adding condition.

Figure 3 shows a side view, broken away in part, .of the feature key locking means of Figur 2 .and certain associated mechanism with the totalizer key in depressed operative position, latched therein with the sub-total and substraction keys locked against being accidentally depressed.

Figure 4 is a view generally similar to Figure 3 and shows onl certain principal parts of the locking means illustrated therein.

Figure 5 is an operational view similar to Figure 3 in which the sub-total key is in depressed operative position, latched therein with the totalizer and subtraction keys locked against accidental operation.

Figure 6 is a view generally similar to Figure 5 and shows only certain principal parts of the locking means illustrate-d therein.

Figure '7 is an operational view similar to Figlire 3 in which the subtraction key is in depressed operative position latched therein with the totalizer and sub-total keys locked against accidental operation.

Figure 8 is a View generally similar to Figure 7 and shows only certain principal parts of the locking means illustrated therein.

Figure 9 is a partial sectional view of the structure of Figure 1 taken along the line 99, as indicated.

Figure 10 is a partial enlarged sectional view taken along the line l6i6 of Figure 1, as indicated.

Figure 11 is a partial sectional view taken along the line H-l l of Figure 1, as indicated.

Figure 12 is a partial sectional view taken along the line iii-i2 of Figure l, as indicated.

Figures 13 and 14 are enlarged elevational views of locking finger plate elements of a key locking unit shown in Figures 2, 4, 6 and 8.

Figure 15 is an enlarged side view of a locking member shown in Figure 1 positioned relative to other cooperative parts of the computing machine.

Figure 16 is a side view broken away in part, of the computing machine which illustrates another form of feature control key locking means constructed according to my invention, that is capable of looking a large number of manually depressible control keys of a machine against operation upon initial operative movement of any one of that number. In this view all keys are shown in normal unoperated positions Figure 17 is a View similar to Figure 16 and shows the locking means withthe totalizer key keys locked.

Figure 21 is a partial sectional View of the looking means and other structure of Figure 16 taken along the line 2 I2l of Figure 16.

Figure 22 is a partial sectional view of the structure of Figure 16 taken along the line 2222 of Figure 16.

Figure 23 is a sectional view of a portion of the structure of Figure 26 taken along the line 2323 of Figure 16.

Figure 24 is a side View of a lock member which forms an element of the key locking means of Figure 16.

Figure 25 is a view similar to Figure 24 and -shows a lock member which is a companion member to that of Figure 25 and forms therewith a locking set to be disposed under each control key.

; Figure 26 is a partial sectional view of the structure of Figure 16 along the line 26--26 as indicated.

' Figure 27 is a right hand side view of the looking means of Figure 16, assembled as a separate unit on a mounting plate detachably fastened on the machine and shown with portions broken away in Figure 16.

Figure 28 is a top view of the structure of Figure 27.

L Figure 29 is an enlarged cross-section along the line 2929 of Figure 27, as indicated.

Figure 30 is an exploded perspective view of the locking means of Figure 27.

My present invention is first described as being carried out in connection with only three feature control keys such as are widely employed in computing machines, Further on in the description, it will be clearly disclosed how my invention, when desired, can be applied to computing or other machines having a much larger number of feature control keys than three.

In carrying out the present invention, a housing A for the adding machine may have a base portion B, a cover portionC and feet D of suitable shape, size and construction such as is illustrated in the drawings.

Numeral keys K projecting above the top of the cover C may be of the same construction and arrangement as is disclosed and claimed in my copendin-g application Serial No. 566,595 or of any other suitable construction and arrangement.

Feature control keys For determining that a desired kind of computation is performed in connection with depressions of selected keys K, I provide means which are controlled by the depression of a certain one of a plurality of feature control keys generally designated as CK. Depression of the key nearest the front of the machine preferably designated T by such a mark on the top thereof, determines that a totalizing operation will be performed. Depression of the next key designated ST determines that a sub=total of a plurality of items will be provided by the machine. Depression of a third key shown (preferably farthest from the front of the machine) designated determines that a subtraction operation will be performed. As will be pointed out hereinafter with more particularity, more than the three feature control keys CK illustrated may be used with my computing machine. Each of these computing operations determined by the depression of a selected control key CK is performed by an operative movement of a rock shaft which may be oscillated by manual operation in a well known way of a pull crank l I or by an electric motor (not shown) which may be drivingly connected to the shaft l 0 and key controlled by means (not illustrated) which may be of a well known construction or as is disclosed and claimed in my copending application, Serial No. 566,595, filed December 4, 1944.

As will be well understood by those skilled in the art, it is desirable to render it impossible to depress any one of the feature control keys CK while my computing machine is then performing an operation previously initiated and controlled by the depression of any of the other control keys. To this end, the keys T, ST, and are mounted on stems l4, l5, and [6 respectively, the upper ends of which project through appropriate holes in the top of the cover C. The lower ends of the stems I4, [5, and I6 may be integrally joined to rearwardly extending levers l1, l8, and I9, respectively. To secure a compact pivotal mounting for these levers having no appreciable side sway or wobble the rear end of lever I9 is preferably securely fastened in a well known way to a sleeve member 20 which telescopes over with a snug working fit a sleeve member 2| to which the lever I8 is securely fastened. The sleeve member 2| in like manner telescopes over a sleeve member 22 to which the lever I1 is securely fastened. The sleeve member 22 has a snug working fit on a shoulder stud 23 which is firmly fastened in a wall element 25 of a frame which may be of the same construction and arrangement as wall element 33 of the computing machine structure of my above mentioned copending application Serial No. 566,595.

An integral depending arm '25 on the end of the lever ll has one end of a pull spring 25 fastened to an outwardly bent end portion thereof, the other end of the spring being fastened to a stud 28 in the wall '24 for swinging the lever H and key T up to normal position after they have been manually depressed, latched, and subsequently released. The levers l8 and [9 may each have a spring powered return means of similar construction to the means described for the lever ll. However, the bent end portion of the depending arm 25 of lever 19 will extend inwardly, and the spring for attachment to a depending arm on lever l8 will be attached directly to the arm. One end of each of these return springs will be fastened to a stud 28. The levers H, [8 and it? may be separated by thin washers 32 and a suitable washer 33 bearing against the outer face of lever H may be securely fastened on the end of stud 23 in a well known way.

First feature control key locking means For latching a manually depressible feature control key in its depressed position, (see Figures 1, 3, 5, and 7) a shoulder latch element 40 may be provided on each of the stems l4, I5, and 5E shaped substantially as illustrated in Figures 3, 5 and 7. A cam formation Al on each element 48 engages the forward edge of an associated slot 42 made in an outwardly bent flange element 43 of a latch plate 44 slidably mounted in a way presently to appear.

Depression of any feature control key moves the plate 34 forwardly against the yielding action of a pull spring 55 having one end fastened to the plate and the other end to a pin in the wall 25. When a square formation on a shoulder elem nt to is moved below the flange 43, the spring moves the latch plate 44 rearwardly and latches the depressed key positively in its operative or down position.

7 In accordance with that feature of my invention which is to make a small initial amount of depression of any one of the feature control keys effective to lock the remaining such keys instant.- ly against being depressed, I provide a unitary feature key locking mechanism L shown in Figures e, 6, and 8 as it appears after having performed different locking functions presently to be explained. In Figure 2, this locking mecha nism L is shown in a normal or inoperative position. It includes a hand-like member 5] (see Figures 13 and 14) which may have a bodyor palm portion 52 of an approximately triangular form converging downwardly made of suitable flat sheet metal and pivoted at its lower end on a shoulder stud 53 in the wall 25. The locking mechanism L also includes a companion sheet metal member 54 with a triangular downwardly converging body 55 pivoted at its lower end on the stud 53 so as to be disposed directly against the body 52. The upper end portion of the body 52 of member BI is widened at each side to provide room for key-blocking finger means cornprising three upwardly extending locking fingers or lugs 55, 5'5, and 58 spaced apart distances corresponding in a way presently to appear to the distances between key stopping shoulder studs 60, 5 I, and 62 strongly and rigidly fastened in the ends of levers l1, l8, and [9, respectively, at right angles thereto. The stop studs 5'3, 5%, and 92 are preferably but not necessarily disposed approximately below the centers of feature control keys designated T, ST, and respectively, and extend toward the center of the machine to terminate a short distance beyond the side wall 212 for a purpose explained hereinafter. Elongated oversize holes 63 are so made in the wall 24 that the stop pins may pass through the wall and be operatively moved up and down without engaging against any edge portion of the wall around the holes.

The finger 56 has an upper end locking edge 65 at substantially right angles to the long axis of the pin and a declining cam edge E55 on the left side (as viewed in Figure 13) of the finger adjacent the upper end. The fingers El and 58 have upper end locking edges 6'1 and E5 respectively, similar to the edge 55. Also the fingers 51 and 58 have cam edges 76 and El, respectively, similar to cam edge 66 but positioned on the right sides of these fingers (as viewed in Figure 13). At the left of the finger 56 and at the right of finger 58 are provided short, stub fingers 12 and 73, respectively, and semi-circular valleys l4 and 15 are provided between the fingers 56 and I2 and between the fingers 58 and [3, respec tively, and these valleys have slightly larger diameters than the pins 65 and 52 which are seated in these valleys when fully depressed. A

stub finger I6 is provided at the right of the finger 51. A semi-circular valley TI is formed between the fingers 51 and 16 for having seated therein the pin SI of slightly smaller diameter. The upper end of the body 55 has a rightward extension to which is integrally joined a locking finger or lug 89 which has a locking edge 8I and a declining cam edge 92 of the same form and size as the locking edge Bi and cam edge I9, respectively. The body 55 also has a locking finger 83 with an upper locking edge 84 and a declining cam edge 85 at the left of the finger 83 which joins the edge 84. The finger 83 is normally disposed adjacent the finger 51 (Figure 2).

For securing a cooperative feature control key locking action of the fingers on the member E with those on the member 54 in a way presently to appear a pull spring 85 has one end fastened to the end of a pin 91 in the body 55 which pin extends outwardly through an elongated.

oversized hole 98 in the body 52. The other end of the spring 86 is fastened to a pin 99 fastened in the body 52. The long axis of the hole 88 is approximately at a right angle to the long axis of the body 52.

For holding the unitary locking mechanism L in proper normal initial work position shown in Figure 2 relative to the pins 99, 9I, and 62, the following described means may be provided. A stud SM is secured to the body 55 at a point on the lengthwise axis of the same a short distance from the stud 53. The head of the stud M is finished smooth and flush with the face of the body 55. Two depending fingers 93 and 94 may be pivotally mounted on the stud 9i against the inner face of the body 55 and held against displacement therefrom by any suitable well known means.

The fingers 93 and 94 may each have a concave edge formation on its inner side which may engage the adjacent side of the stud 53 in normal position (Figure 2) as will presently appear. A pin 95 for cooperation with the fingers 93 and 94 is fastened in the wall 24 below the stud 53 centered on an imaginary plane passing through the axis of the stud 53 and the stud 9I when the locking mechanism L is in its normal or starting position as illustrated in Figure 2. A pull spring 96 has one end fastened to an integral lug on the finger 93 and the other end to a like lug on the finger 94, this spring being positioned below the lower ends of the bodies 52 and 55.

The three fingers 55, 57, and 58 on the plate 55 provide a complement of blocking components 95, 61, and 98 respectively associated with the blocking parts 59, 9I, and 62 on the key stems I4, I5, and I6. Similarly, the fingers 99 and 93 on the plate 54 provide a complement of blocking components 8i and 84 respectively associated with the blocking parts 9| and 92 on the key stems I5 and I6.

Second feature control locking means To secure that object of my invention which is to provide a second locking means for the feature control keys, the slidable latch plate 44 mounted as is described hereinafter has a body element I9I disposed in a vertical plane between the wall 24 and the adjacent wall element of the cover C. The bent out integral flange element 43 is disposed at approximately right angles to the body IM and to the stems of the feature keys T, ST and The lengthwise locking slots 42 are positioned in the flange 43 as shown in Figure 9, and each key stem I4I5--I5 extends upwardly from its associated lever I'I, I8 or I9 through its associated slot 42 to have the lower portion of the 'cam formation on each keystem disposed'in its associated locking slot when the associated lever is stopped against the flange 43. The pull spring 59 iseifective normally to keep the metal at the forward end of each slot 42 against its associated key stem. As pointed out above, while any feature control key is being depressed its cam formation 4i moves the plate 44 and body I 9| forwardly until the shoulder element 49 is below the flange 43 whereupon the flange element at the end of the slot associated with the depressed feature key is moved by the spring 59 over the shoulder to hold the key in its down position. For locking the flange 43 in operative engagement with the stem of the depressed key and over its shoulder 49 a transversely bent integral lug I96 is provided on the rear end of the flange (see Figure 9). A short lever member I97 pivotaly mounted on a shoulder stud I98 in the wall 24 has a notch I99 positioned to receive the lug I96 when the lever is swung up to locking position by means presently to be described.

To provide a slidable mounting for the member '44 that has but little friction and other advantages soon to appear (Figures 1, l1 and 12) the body I9! has a forwardly projecting plate element I I9 disposed in a slot II I, the length of which is materially more than the width of the plate element I59, this slot being provided in a flange element II 2 of a sheet metal member I is fastened to the wall 24. To maintain the plate I I9 in a feating relation to the ends of the slot I I I and spaced therefrom, the lower. end of an upright lever IE9 may be pivotally mounted on a sleeve carried by a stud IE5 in the plate 24 and the upper end of the lever is pivotally fastened to a shoulder stud I'IS mounted in the body IN. The rear end of the body IElI may be slidably mounted on a shoulder stud II! (Figure 1) fastened in the wall M which stud, if desired, may carry antifriction means (not shown) of well known construction and project through a slot I I8 in th body I9l with a running fit.

For moving the locking plate 44 forwardly to disengage it from the shoulder of a depressed control key and the stems of undepressed control keys, a trigger member H9 (Figures 1 and 11) may be pivotally mounted on a shoulder stud fastened in the body HM and have a transversely bent integral lug H9 engaging under the lower edge of a lug I29 on the body I9I. To hold the trigger yielding in normal position, a pull spring IZI has one end fastened to an ear I22 on the trigger and the other end fastened to an ear I23 on the lever H4. The rear end of the trigger H9 has a cam edge I24 for engagement with a part presently to be described. Holes I25 are provided in the body I9I to permit the studs 59, BI, and 52 to pass through the body and have adequate clearance for their operative movements and to permit full operative movement of the locking flange 43 without interference from these studs.

To accomplish that object of my invention which is to lock the unoperated feature control keys against depression by a second locking means after only a small initial operating move ment of the computing machine under control of a depressed control key has taken place, the following described mechanism may be employed. The rock shaft I9 may have mounted thereon an oscillatable member I26 having a shoulder stud I2! mounted in its outer end. A cam roller (not shown) may be mounted on the stud I21 for engagement in a cam slot I28 in a rockerarm I30 pivotally mounted on a shoulder stud |3| in the wall 24. The arm I30 has a short upwardly inclined extension I32 on the end of which is mounted a stud I33. The pivoted arm I07 has a cam slot I34 acted on by the stud I33 for raising the arm I01. The arm I01 also has a looking notch I09 for receiving the lug I06 and holding the latch plate 44 in one position, as eX- plained hereinafter.

The lower end of the rocker arm I30 has gear teeth for engaging with a gear sector I35 on a main operating shaft I36 of the computing machine. The lower slotted and toothed portion of the rocker arm I30, the gear I35 and shaft I36 may be of substantially the same construction and arrangement as disclosed for like parts in my above noted copending application Serial No. 566,595.

The rocker arm I30 has anupwardly and forwardly inclined integral arm I3'I which carries at its upper end a cam roller I38 on a shoulder stud in the arm I3I. The cam roller I35 is positioned for engaging the cam edge I24 on the end of the trigger ||9 upon movement of the roller as the rocker arm I30 makes a clockwise return move ment by operation of the handle II or other means. The roller I38 moves the trigger H9 idly out of the way on its counter-clockwise movement. It will be noted that the cam roller I38 does not move the trigger H9 and locking flange 43 until after the locking notched lever I! has been disengaged from the lug I06. It is to be understood that the shaft I0 may be connected in a suitable well known way with an electric motor (not shown) controllable in a well known way by any of the control keys for driving my computing machine.

Operation of feature control key locking means In Figure 2 the studs 60, BI, and I52 and unitary locking mechanism L are shown in normal or inoperative positions. Should the totalizer key T be depressed (Figures 3 and i) its stud 60 engages the cam edge 66 and swings the entire member rightwardly i. e., rearwardly enough to bring the locking lug edges 5'! and [58 directly under and in very close proximity to the studs GI and 62 of the keys ST and This locking movement of the member 5| is accomplished during the first part of the depression or operative movement of the key T. The member 54 is moved clockwise too by action of the spring 85 pulling the pin 8'! up against the left end of the slot 88. The finger 93 is bodily moved slightly clockwise about the stud 53 and away from the pin 95 against the pull of the spring 96 which also functions to swing the body 54 counter-clockwise when the key T is raised again. The springs 86 and 95 thus cooperate in tending to return the locking mechanism L to normal position (Figure 2) As the key T is depressed the flange 43 and lug I06 of the latch plate 44 are cammed forward, and then returned to Figure 2 position by the spring 50. As the pull crank II and shaft I0 begin to move co-unter-clcclnvise the stud H3 acting in cam slot I34 raisesthe arm I01 and disposes the notch I09 in looking engagement with the lug I 06 and holds it there until the end of the return movement of the shaft |0- has been largely completed.

when the return movement of the shaft I0 and the slotted rockable member [30 have been completed enough to disengage the notch I09 from the lug I06, the cam roller 138 will be n iii to engage the cam edge I24 on the trigger H9 and thus move the flange 43 out of locking engagement with the shoulder of key T which instantly rises to starting position. Thereupon the locking mechanism L returns to normal (Figure 2) position. 7

When the key ST is depressed (Figures 5 and ,6), the lug 5| engages both cam edges I0 and 85 and moves the fingers El and 8.3 apart which swings the finger edge under stud 6!! and the finger edge 8| under the stud 62 of the key The operation and release of the parts of the second locking means are the same as described above in connection with the locking of the key T.

When the feature control key is depressed (Figures 7 and 8), its stud 52 will engage the cam edges II and 82 and swing the members 5| and 54 counter-clockwise and move the finger 56 under the stud 60 of the key T and bring the finger 83 under the stud 5| of the key ST. The operation and release of the parts of the second looking means are the same as described above in connection with-the locking of the key T'except as follows. The finger 94 is moved counterclockwise away from the pin 95 and the finger 93 is held against the pin 95 by the spring 96 which is under a tensile strain. This will swing the member 54 clockwise to Figure 2' position when the key is raised. The spring then is effective to pull the member 5| clockwise to normal (Figure 2) position.

It will appear from inspection of Figure 9 and consideration of the above description that a depressive force on the unoperated and locked control keys will ordinarily be resisted first by the second locking means and very shortly thereafter by the first locking means. This'will occur because the studs 60, EI and 62, in practice;

may not be actually touching the associated locking fingers in locked condition. The locking flange 43 however is ordinarily spring urged into engagement with the key stems associated with the studs 50, BI and 62.

It can be seen by inspection of Figures 1 and 2 that should a depressive force be exerted on the control keys T and ST at the same instant the studs 60 and 6| will engage oppositely sloped cam edges 66 and is on one piece of metal and the member 5| will not be moved in either direction and will prevent the operative movement of key T and/or key ST.

In like manner simultaneous depressive forces on the control keys T and will be resisted by oppositely sloped cam edges 55 and 'II' and I fail to move the member 5! and thus cannot be operated. Should simultaneous depressive forces be applied to control keys ST and the studs EI and 52 will engage the oppositely sloped cam edges 82 and 85 and fail to swing the member 54 and its fingers out of their work paths which will thus prevent their operative depression together. It can be further seen that attempted operation of two control keys at onetime will not permit either to be depressed enough to be latched in its down or operative position or to be depressed more than a negligible amount.

In Figures 16, 1'7, 18, 19, and :20 are illustrated structures which show how I may accomplish that object of my invention which is to provide means which can look all of the unoperated keys of a large number of feature control keys against operation upon small initial operative movement of any one of the number. In these views, there are shown a totalizer key T, a sub-total key ST, a subtraction key and a non-add key which 11 may bear the indicia NA. The construction of the keys T, ST, and together with their associated stem members I4, I5, and I6 and offset shoulder elements 40 and cam formations 4| may be the same as described hereinbefore. The key NA may have a stemlt and a shoulder element 40 and a cam formation II thereon substantially as shown in Figure 16 for cooperation with parts hereinafter described. The stem I4 is integrally joined to a lever I! of the construction described hereinbefore. The stems I5 and I6 may be integrally joined to rearwardly extending levers I8 and I9 of the shape shown in Figures 16 and 21 or of the shape substantially as is shown in Figure 1. In the Figure 16 structure, the levers I8 and I9 are shaped to be positioned with relation to other parts of the computing machine not shown in Figure 16. The stem I6 may be integrally mounted on a lever I50. The levers I'I, I9 and I9 may be pivotally mounted on telescoping sleeve members carried by the stud 23 as is described hereinbefore. The lever I50 may be mounted on a sleeve I5I which telescopes over the sleeve 29. Return springs 26 for the levers I1, I8 and I9 may be of the same construction as disclosed hereinbefore but to permit an additional return spring 26' for the lever I59 to be fastened to the stud 28 and to an arm of the lever I56, the depending arms 25may be arranged slightly differently from the way shown in Figure 10, this different arrangement beingshown in Figure 23. Lock engaging studs 60, 6| and 62 may be mounted in the levers I1, I9 and I9 substantially as is described hereinbefore, and a like lock engaging stud I52, except that it is shorter than the studs 60, 6| and 62', may be mounted in the lever I under the key NA.

Locking means for coaction with the studs 69, SI, 62 and I52 regardless of their number, which will prevent all of the unoperated control keys being depressed after one of such keys has been initially depressed a small amount may be constructed as follows according to my invention. A key lock set generally designated as I55 is provided for cooperation with the locking stud associated with each control key and includes upright sheet metal key-blocking finger means comprising members I56 and I5! (see Figures 22, 24, 25, 2'7, and 30). Since these sets may be of the same construction except as appears hereinafter and have the same or similar functions, only one set needs to be described for an understanding of this feature of my invention. A lower portion of the finger member I56 may be slightly inclined to the right and have a mounting hole I58 and another hole I60. Above the hole I69, the finger I56 is shown with a considerably enlarged, i. e., widened out portion I62 with much of the same cut away to leave a relatively large hole I63 through the finger which will permit full operative laterally reciprocable movement of the finger when other parts of the computing machine (not shown) are disposed in the hole I63. It will be understood as the description proceeds that in using my locking means in some machines, the enlarged finger portion I 62 and hole I63 may be omitted from some or all of the locking fingers. Above the widened out portion I62 is provided a finger tip portion I65 which may have a straight transversely disposed stud engaging edge I 66 and a downwardly and leftwardly inclined cam edge I61.

The finger member I51 (Figure 25) may have a form similar to that of the finger I56 with 12 which it has a cooperative paired relation. It will be noted, however, that these fingers I 59 and I5? are not exact duplicates, although the finger I51 may have elements such as a mounting hole I68, a hole ITO, a widened portion IE2, a hole therein I I3, a finger tip portion IE5, a transverse lockin edge I16 and a cam edge II'I which function similarly to corresponding elements of the finger I 56. The design of the fingers I56 and I5! is, advantageous in that one set of die tools can be employed for stamping out both fingers of a set from sheet metal each finger to have finger tip elements I65 and I15, one of which will be sheared off. As will presently appear, in some of the sets I55 of locking fingers two finger tip elements with their cam edges in the same plane normally will be needed. In other sets one of the finger tips of each of such sets will be oppositely disposed from the other finger tip as regards their inclined cam edge elements.

One of the sets I55 is mounted under each of the studs in the feature control ke levers. Both of the fingers I56 and I5! of each set are pivotally mounted for easy oscillatory movement on a shoulder stud I89 firmly secured to a mounting plate I8I which may be fastened on the wall 24 by screws I82. All of the outwardly disposed fingers of the several sets are interconnected one with the others, by a link member I83 and a short shoulder stud I84 for each finger, which stud has a head element I85 which is seated with a snug working fit in the associated hole I69 in the finger. The head of each stud I 912 is disposed slightly inward from the adjacent face of the associated finger so that it cannot interfere with the movement of the other finger of the set. All of the inwardly disposed fingers of the several sets are interconnected, one with the others, by a link member I81, and studs I99 of like construction to that described above for the link member I93 and the studs I84. The fingers I56 and I5! may be fastened on the studs I89 and to the links I83 and I3! and disposed in spaced relationship to the plate I8I by suitable devices of well known construction, as is illustrated in Figure 30, and a further description of these devices appears unnecessary.

In accordance with that feature of my invention which is to provide unitary means for returning all of the locking fingers to normal inoperative positions after each depression of a control key, the following described structure may be employed. A rearward integral extension of the link I83 is fastened loosely by a headed pin I90 to a normalizing mechanism I9I. This may include a depending arm I92, and a depending arm I93, each pivotally fastened on the pin I96, and each arranged with a concave side edge element which bears against a stud I99 mounted in the plate I 8|. Adjacent the'lower end of each arm I92 and I93 are bent out in tegral lugs I95, which are connected by a pull ing mechanism I9 I, and to return these inwardly disposed fingers to their normal, inoperative positions, a forward integral extension of the link I8! is loosely fastened by a pin 269 to a normalizing mechanism I the parts of which may be duplicates of the corresponding parts of the mechanism I9I. However, the mechanism 26I is turned upwardly instead of downwardly to avoid interference with parts of the computing machine (not shown). The mechanisms I9I and 2!lI as is shown in Figures 17, 18, 19, and 20 function in a similar manner to the functionin of the normalizing mechanism employed in connection with the locking device L described hereinbefore, except as appears hereinafter. It will be noted that all of the sets of locking fingers and the two normalizing mechanisms including the cooperating studs I94 and pins I91 and mounting plate I8I constitute a sub-assembly or unit (see Figures 27 and easil attached to the wall 24 or removed therefrom.

When four feature control keys are employed according to my present invention, the stems of the keys T, ST, and may extend upwardly through the slots 52 provided in a modified flange 43. For locking the key NA by action of the flange 43, instead of extending the flange considerably to the rear to provide room for another slot 42, a deep, narrow ldcking notch 262 may be provided in the rear end of the flange 43 and a larger cam formation 4! than the cam formations AI is provided onthe forward end of the lever I56 for engaging against the metal at the forward edge of the notch 262. The other parts of the feature key locking means associated with the flange 43 may be of the same construction and arrangement as is described hereinbefore in connection with the flange 43, except that a pivoted locking lever arm 20A. is longer than the similarly functioning lever I61 and a stud 265 for mounting the lever 264 is shorter than the stud I68 for the lever I01. i

The four fingers I56 constitute a complement of blocking components, including components I66-I 66 respectively associated with the blocking parts 60 and I52 on the ke stems I4 and I6, and components I16-I16 respectively associated with the blocking parts 6| and 62 on the key stems I5 and I6. Similarly the four fingers I51 constitute a complement of blocking components, including components I66-I66 respectively associated with the blocking parts 66 and SI of the key stems I4 and I5, and components I16--i16 respectively associated with the blocking parts 62 and I52 on the key stems I6I6'.

Functioning of multiple sets of interconnected locking fingers In Figure 16, the normal inoperative or starting position of the sets I55 of key locking fingers I56 and I51 is shown. It will be noted that in the sets associated with the T and control keys, the inclined cam edges I61 and I11 are disposed in the same plane. Also it will be noted that in the alternate sets of locln'ng fingers associated in the present application with the control keys ST and NA, the inclined cam edges I61 and I11 are disposed in planes which intersect each other at a relatively small angle. The mechanisms HM and 265 which have a double function of retaining each of the sets I 55 in normal, inoperative positions and of restoring all of the sets to normal position after any con- F trol key has been depressed and returned to its normal upper position, are disposed in starting positions so that the pin I96 is in alignment with the fixed studs I94 and I91. The mechanisms I9I are efiective to require approximately an equal amount of depressive force to move operatively any of the locking finger sets I55, irrespective of the number of such sets interconnected with each other and the equalizing mechanisms I9I. It can be seen from inspection of Figures 16, 1'7, and 19 that depression of either the first (T) or third control key makes the associated locking stud engage both cam edges I61 and I1! at the same instant and swing their associated fingers and the interconnecting links I83 and I81 in the same direction. Also, it will be seen from inspection of Figures 16, 18, and 20 that depression of either the second (ST) or fourth (NA) keys makes the associated stud engage both cam edges I61 and I11 at the same time and swing their associated fingers and the interconnecting links I83 and I81 in opposite directions.

Upon a small initial depressive movement of control key T (see Figures 16 and 17) a locking edge I16 is swung under the lock studs 6| and I52 of the keys ST and NA, respectively, and two locking edges I16 are swung under the stud 62 of the key and these keys cannot be depressed until the computing machine has completed an operation under control of the key T. Upon a small initial depressive movement of the control key ST (see Figures 16 and 18) a locking edge I66 is swung under the stud 66; a locking edge I16 is swung under the stud 62, and locking edges I66 and I16 are swung under the stud I52, and their associated control keys cannot be operated. Upon a small initial depressive movement of the key (see Figures 16 and 19) two locking edges I66 are swung under the stud 66, and one locking edge I66 is swung under each stud SI and NA and their associated control keys cannot be operated. Upon a small initial depressive movement of the key NA (see Figures 16 and 20) one locking edge I66 is swung under the stud 60, looking edges I66 and I16 are swung under the stud 6|, and one looking edge I16 is swung under the stud 62, and their associated control keys cannot be operated.

By inspection of Figure 16, it can be seen that should an attempt be made accidentally or otherwise to depress the control keys T and ST for example, at the same instant, the stud 60 will engage the outer inclined cam edge I61 thereunder and the stud 6| will engage the oppositely inclined cam edge I11 thereunder. Since these edges are on looking fingers connected by a portion of the unyielding inner link member I81 they cannot move out of the Way of the studs and thus prevent the depression of either of these studs or the control keys connected therewith. In like manner, attempted simultaneous depression of the keys T and will be prevented by the associated studs 66 and 62 engaging against oppositely inclined cam edge I61 and I11 of the associated fingers which are connected by an unyielding portion of the outer link I83. The attempted simultaneous depression of the keys T and NA will be prevented by engagement of the associated studs 66 and I52 with oppositely inclined cam edges I61 and I11 on fingers connected by a portion of the inner link I81. Attempted simultaneous depression of the keys ST and will be prevented by engagement of the associated studs 6| and 62 with oppositely inclined cam edges I61 and I11 on fingers connected by a portion of the inner link I81. Attempted simultaneous depression of the keys ST and NA will be prevented by the associated studs 6| and I52 engaging oppositely inclined cam edges I61 and I11 of fingers connected by a portion of the link E83 and a portion of the link I87. Attempted simultaneous depression of the keys and NA will be prevented by the engagement of the studs 62 and H52 engaging against oppositely inclined cam edges l6! and ill on fingers conencted by a portion of the link member 183. It can be seen that a small extent of depressive movement of two control keys may take place when a depressive force is applied simultaneously to the two keys but this movement will be so small as to be negligible. Since no two control keys can be simultaneously depressed on a computing or other machine equipped with my locking means described hereinbefore, it can be readily seen that simultaneous depression of three or more control keys will also be prevented according to my invention.

From a consideration of the disclosure hereinbefore, it can be seen that the arrangement of the sets of locking fingers interconnected by imyielding links with equalizing devices can be extended for making use of any number of locking fingers likely to be needed in connection withthe operation or control of any key operable or key controllable machine. It can also be seen that the number of such locking fingers interconnected by a single link can be increased and/or the number of interconnecting links arranged side by side can be increased. Also, it will be understood that one element of the interconnection of two different locking fingers is found in the locking studs in the control key lever involved. It can be readily seen, however, that in some cases the locking stud may be omitted and the key stems or levers can be so formed as to be operatively engaged by the locking fingers upon depression of the associated keys.

The feature control keys T, ST, and NA may be operatively connected with associated parts of the accumulator mechanism of my computing machine through depending links'25ll, 251, and 252 having lost motion connections with the key levers in the form of short lengthwise slots 250 in the links through which flanged studs fastened in the levers may project. lhe construction and operation of the connecting levers 250, 25! and 252 are described with more particularity and claimed in my copending application, Serial No. 650,010, filed February 25, 1946.

The feature control keys T, ST, and may be operatively connected with a printing device 255 through means of the studs 60, 6!, and 62 engaging with a slidable rack member 256. The construction and operation of the printing devices 255 and the operative connections of the feature control keys CK therewith are described with more particularity and claimed in my copending application Serial No. 650,010, filed February 25, 1946.

Certain of the advantages of the present invention will appear from a reading of the foregoing description. Other advantages arise from the employment of the slideable key locking member for arresting the upward movement of the keys when they are released to be moved upwardly by their return springs.

Other advantages arise from the provision of lengthwise slots in the links which connect the levers of the feature control keys with parts of the accumulating mechanism of the computing machine. This construction helps to assure that the undepressed keys will be locked against accidental depression before mechanism under control of a selected feature control key will be affected by depression of such key, especially in motor driven computing machines embodying my invention.

Still other advantages arise from the provision of a key locking mechanism operable by depression of a selected feature control key for locking a plurality of undepressed keys, which mechanism is of a design that can be constructed to take care of additional depressible keys where more than three are employed.

Although I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and systems.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a computing machine, the combination of a plurality of depressible feature control keys, upwardly urged levers associated with said keys, one of said keys being mounted on an end of an associated lever, a locking stud for each of said keys in each of said levers transversely disposed thereto under its associated key, and key operable means for locking any of the remaining unoperated control keys against depression upon the depression of a selected control key, said key operable means including a fixed pivot member in said machine lower than said lever carried studs, a first upright plate member pivotally mounted on said fixed member, a second upright plate member pivotally mounted on said fixed member contiguous to said first plate member, a plurality of upreaching finger-like members on said first plate member, each of said finger members having a downwardly sloping cam edge disposed under and closely to one of said lever carried studs, each of said finger members having a locking edge movable under the associated lever carried stud, said second plate member having a plurality of upreaching finger members each having a sloping cam edge and a locking edge of similar construction to the cam edges and locking edges of said first plate member,at least one of the cam edges of said second plate member being sloped downwardly in the opposite direction to the cam edge of an adjacent finger on said first plate whereby a superposed associated lever carried stud when depressed will move one plate in one direction and the other plate in the opposite direction for the key locking purposes set forth, spring operated means carried jointly by said first and second plate members which tend to return said plate members toward each other and to normal starting positions on said pivot member after any depressed lever carried stud is raised clear of said key operable locking means, the construction and arrangement of the cam edges and locking edges on the fingers of both plates being effective upon the depression of'any selected key to cam the locking edge of at least one finger of one of the two plate members under each undepressed lever carried stud.

2. In a computing machine, the combination of three depressible keys each having a blocking part; and locking means for preventing depression of any undepressed key when any other of said keys is in depressed position, comprising a first plate having three blocking components and three cam surfaces respectively contiguous thereto, means mounting said first plate in a normal position in which two of said blocking components 

